CASA have made the Point that calling in the turn presents a more visible aircraft, because the wings are banked. The way I read the latest attitude to this is leave it to the pilot rather than prescribe. I don't think. I've ever gone into a circuit with a SPECIFIC number of radio calls in my mind. You accommodate to the circumstances with the aim of knowing where any conflicting aircraft is and not transmit any longer than absolutely necessary, and don't give any erroneous calls. ALLOW for faster aircraft making a straight in approach .Nev